A geographic information system (GIS) integrates hardware, software, data, personnel and procedure for capturing, managing, analyzing and displaying all forms of geographic information. It is a technological tool for comprehending geography and making intelligent and smart decisions.

GIS organizes geographic data so that a person reading a map can select data necessary for specific project or task. A thematic map has a table of contents that allows the reader to add layers of information to a base map of real-world locations.GIS can be integral to fashioning system based solutions to our environmental challenges.

Relevance of GIS maps over traditional maps
Creation of traditional paper maps are costly and time consuming. It is difficult to combine and store large volumes of data associated with the map while in GIS maps huge amount of data can be added as attribute information which can be easily retrieved, manipulated, updated and analyzed. It is possible to integrate GIS maps with satellite imagery so that spatio- temporal analysis can effectively be done.

Process in GIS

Process in GIS involves the following
1. Procurement of spatial data
2. Projection
3. Geo-referencing and Vectorisation
4. Creation of Topology and Editing
5. Addition of attribute information
6. Analysis
7. Creation of maps and presentation of results

Application of GIS
Geographic information system has versatile applications. Apart from environmental management, it can be used for business studies, disaster management studies, pollution studies. It is a powerful tool for precise and objective decision making with great amount of transparency and accountability. The main draw back of developmental decision making is its arbitrariness and subjectivity which can easily be overcome by GIS enabled objective decision making and hence for attaining environmental efficiency, application of GIS is invariably required.